LIPEMIA (lipaemia; grech, lipos fat + haima blood) — availability of fat (neutral fats or triglycerides) in blood. The concept «Lipemia» in daily a wedge, practice is quite often used in sense by «hyperlipemia», i.e. the increased content of fat in blood, or even identify with the term «lipidemia» that is not absolutely correct since the concept «lipidemia» includes not only gipertriglitseridemiya) that is characteristic of L., but also hypercholesterolemia (see).
The lipemia is characterized by the fact that plasma (or serum) blood has opalescent milk (sometimes cream) the color long since observed by doctors during the bloodletting. In 1774 Mr. W. Hewson established that high concentration of fat (i.e. triglycerides) in blood is the reason of it.
However considering that all lipids of a blood plasma, including triglycerides, are in it not in a free look, and as a part of difficult lipidobelkovy complexes — lipoproteids, it is possible to say that the reason of L. accumulation in blood serum of the lipoproteids rich with triglycerides is — chylomicrons or lipoproteids of very low density or that and others at the same time. Accumulation of these classes of lipoproteids in blood serum gives it a look, characteristic of linden-michesky blood serum. Strengthening of triglycerides in blood (norm of 50 — 190 mg of %) always accompanies L. The lipemia is a characteristic sign of some types of giperlipoproteinemiya, napr, giperlipoproteidemy I, IV and V types (see. Lipoproteids ).
Reasons of development of L. can be various. In fiziol, conditions of L. it is observed after reception of greasy food (alimentary L.) also it is characterized by emergence in a blood plasma of chylomicrons (serum chylosum). Alimentary L. reaches a maximum in 3 — 6 hours after reception of greasy food and stops in 8 — 10 hour. Reason of L. there can be also strengthening of mobilization fat to - t from fat depos (L. at starvation, blood loss, and also at heavy anemias of various origin, a diabetes mellitus, pancreatitis, damages of kidneys with a nephrotic syndrome, glycogenoses), genetically caused insufficiency of a lipoproteidlipaza (a family hyper-chylomicronemia), the strengthened formation of lipoproteids of very low density or the slowed-down their catabolism (at various diseases of parenchymatous bodies, alcoholism, poisonings etc.). Moderated by L. it is observed also at pregnancy owing to increase in content in blood of lipoproteids of very low density.
If L. is followed by accumulation only of chylomicrons, after standing of blood serum during the night in the refrigerator homogeneous liquid is divided into two layers: upper, slivkoobrazny, and lower, transparent. At high content in blood serum of lipoproteids of very low density for lack of chylomicrons blood serum even after long standing in the refrigerator continues to be homogeneous muddy. At simultaneous high content in blood serum of chylomicrons and lipoproteids of very low density emersion of chylomicrons and preservation of a turbidity in a sublayer of liquid is observed. The test of «standing of serum in the refrigerator» is widely used in laboratory diagnosis during the phenotyping of giperlipoproteinemiya.
At healthy faces alimentary L. easily is eliminated with intravenous administration of heparin which activates enzyme to a lipoproteidlipaz (see) what the enlightenment of plasma is result of (therefore heparin is called sometimes a factor of an enlightenment). Treatment of the basic disease which led to L., it is carried out taking into account established like a giperlipoproteinemiya (see. Lipoproteids, disturbances of lipoproteidny exchange ).
See also Lipometabolism .
Bibliography: Lipids, under the editorship of S.E. Severin, page 103, M., 1977, bibliogr.; Phenotyping of giperlipoproteidemiya, sost. A. N. Klimov, etc., M., 1975; Lipids and lipidoses, ed. by G. Schettler, B., 1967; Treatment of the hyperlipidemic states, ed. by H. R. Casdorph, Springfield, 1971.
A. H. Klimov.